--- a/toolkit/components/extensions/schemas/notifications.json
+++ b/toolkit/components/extensions/schemas/notifications.json
@@ -181,16 +181,17 @@
     "functions": [
       {
         "name": "create",
         "type": "function",
         "description": "Creates and displays a notification.",
         "async": "callback",
         "parameters": [
           {
+            "optional": true,
             "type": "string",
             "name": "notificationId",
             "description": "Identifier of the notification. If it is empty, this method generates an id. If it matches an existing notification, this method first clears that notification before proceeding with the create operation."
           },
           {
             "$ref": "CreateNotificationOptions",
             "name": "options",
             "description": "Contents of the notification."

--- a/toolkit/components/extensions/test/mochitest/test_ext_notifications.html
+++ b/toolkit/components/extensions/test/mochitest/test_ext_notifications.html
@@ -15,17 +15,17 @@
 add_task(function* test_notification() {
   function backgroundScript() {
     let opts = {
       type: "basic",
       title: "Testing Notification",
       message: "Carry on",
     };
 
-    browser.notifications.create("", opts).then(id => {
+    browser.notifications.create(opts).then(id => {
       browser.test.sendMessage("running", id);
       browser.test.notifyPass("background test passed");
     });
   }
 
   let extension = ExtensionTestUtils.loadExtension({
     manifest: {
       permissions: ["notifications"],